NASHVILLE, Tenn. (AP) — Police are warning residents of a Nashville neighborhood to watch out for a suspect in a Waffle House restaurant shooting that killed four people.

Authorities say more than 80 Nashville police officers continued to search for Travis Reinking early Monday.

Agents with the FBI, the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives and troopers with the Tennessee Highway Patrol were also assisting in the manhunt as disturbing reports about Reinking's past behavior came to light.

Officials with the Nashville public school system say schools will go into "lock-out" mode if Reinking isn't found in time for class Monday.

Police say Reinking was nearly naked and brandishing an assault-style rifle when he opened fire in the parking lot and then stormed the restaurant. Four people killed, four others were injured.